soc/intel/skylake: Make use of common thermal code for SKL

This patch ensures skylake soc is using common thermal code
from intel common block.

TEST=Build and boot soraka

Change-Id: I0812daa3536051918ccac973fde8d7f4f949609d
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34648
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Aamir Bohra <aamir.bohra@intel.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/intel/skylake/chip.h

@@ -585,9 +585,6 @@ struct soc_intel_skylake_config {
 	 */
 	u8 IslVrCmd;
 
-	/* PCH Trip Temperature */
-	u8 pch_trip_temp;
-
 	/* Enable/Disable Sata power optimization */
 	u8 SataPwrOptEnable;
 };